package com.justnow.offer;

import java.util.Scanner;
/**
 * @author justnow
 * Created on 2020-09-07
 * Description
 *
 * 线性魔塔
 *
 */
public class Beike04 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int[] down = new int[2 * n];
        int[] up = new int[2 * n];
        for (int i = 0; i < 2 * n; i++) {
            down[i] = scanner.nextInt();
        }
        for (int i = 0; i < 2* n; i++) {
            up[i] = scanner.nextInt();
        }
        int sum = 0;
        int middle = n / 2;
        if (n % 2 == 0)
            middle = n / 2 - 1;
        else
            middle = n / 2;
        for (int i = 0; i <= middle ; i++) {
            sum -= down[i];
            sum += up[i];
        }

        for (int i = middle + 1; i < 2 * n; i++) {
            sum -= down[i];
            sum += up[i];
        }
        System.out.println(-sum + 1);
    }
}
